A known fiber-bale mill may comprise a milling cutter member which travels to and fro over a row of fiber bales and a fixed collector for collecting said fibers. The cutting member comprises at least one cutter roller, and an air passage through which the fibers cut are drawn pneumatically into said collector.
It is known to provide a grid through which the fibers from the upper surface of the fiber bale can reach the cutter roller, and which is inclined to the horizontal and leads in the region under the axis of the cutter roller, in order to press the fibers under the cutter roller.
With this cutter mechanism, rows of fiber bales can be cut, only if their top sides lie in a plane, that is, they must be of the same height. If the fiber bales to be cut have different heights, which occurs most commonly when fibers of bales from different sources are to be mixed, then the height of the cutting device must be changed or the higher fiber bale must be reduced to the height of the lower fiber bale by removal of the excess fiber.